Traction device adjustment mechanism and method

ABSTRACT

In one embodiment, a method is provided for adjusting the length of a belt having right and left front portions and a back portion, the right and left front portions of the belt each moveable with respect to the back portion of the belt. Opposite ends of a strap are attached to the right and left front portions of the belt. The strap includes a middle section including opposing portions detachably coupled to one another. The strap is coupled to the back portion of the belt between the opposite ends of the strap such that movement of the right and left front portions of the belt away from the back portion of the belt causes detachment of the opposing portions of the middle section of the strap from one another. The right and left front portions of the belt are moved away from the back portion of the belt to adjust the length of the belt, the detachable coupling of the opposing portions of the middle section of the strap ensuring that the right and left front portions of the belt move in approximately equal amounts relative to the back portion of the belt.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.09/875,315 entitled “Traction Device Adjustment Mechanism and Method”filed Jun. 5, 2001, now U.S. Pat. No. 6,635,025 which claims the benefitof Provisional Application No. 60/272,821, filed Mar. 1, 2001.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the field of medical devices, and moreparticularly to a traction device adjustment mechanism and method.

BACKGROUND OF THE INVENTION

People have long dealt with the pain, aggravation and loss ofproductivity arising from spinal injuries, particularly those to the lowback. Most people at some point in their lives will be incapacitated bylower back pain that has become the second leading cause of pain next toheadaches. The relative ease with which injuries to the spine andsupporting musculature are incurred, as well as the debilitating effectsof even slight injuries, merely adds to the overall severity of theproblem of dealing with spinal injuries. The forms of treatment varyover the length of time that the patient experiences pain. Eightypercent of low back pain suffers will heal over six weeks with minimalintervention. However, the remaining twenty percent of sufferers createthe greatest challenges and cost to the medical system. After the acutephase, surgical intervention or more invasive forms of treatment may beselected. Minimal or non-invasive treatment methods are howeverpreferred by patients before electing to surgical methods.

SUMMARY OF THE INVENTION

According to the present invention, certain disadvantages and problemsassociated with previous methods for treating the spine may be reducedor eliminated.

In one embodiment, a method is provided for adjusting the length of abelt having right and left front portions and a back portion, the rightand left front portions of the belt each moveable with respect to theback portion of the belt. Opposite ends of a strap are attached to theright and left front portions of the belt. The strap includes a middlesection including opposing portions detachably coupled to one another.The strap is coupled to the back portion of the belt between theopposite ends of the strap such that movement of the right and leftfront portions of the belt away from the back portion of the belt causesdetachment of the opposing portions of the middle section of the strapfrom one another. The right and left front portions of the belt aremoved away from the back portion of the belt to adjust the length of thebelt, the detachable coupling of the opposing portions of the middlesection of the strap ensuring that the right and left front portions ofthe belt move in approximately equal amounts relative to the backportion of the belt.

In another embodiment, a method is provided for fitting an ambulatorytraction device to a user. Two or more support belts are positionedaround the user's body, each support belt including a back portion andright and left front portions. The length of at least one of the supportbelts is adjusted by attaching opposite ends of a strap to the right andleft front portions of the belt, the strap having a middle sectionincluding opposing portions coupled to one another, and guiding thestrap using a strap guide coupled to the belt proximate to the backportion. The strap is coupled to the back portion of the belt betweenthe opposite ends of the strap such that movement of the right and leftfront portions of the belt away from the back portion of the belt causesdetachment of the opposing portions of the middle section of the strapfrom one another. The right and left front portions of the belt aremoved away from the back portion of the belt to adjust the length of thebelt, the detachable coupling of the opposing portions of the middlesection of the strap ensuring that the right and left front portions ofthe belt move in approximately equal amounts relative to the backportion of the belt.

In another embodiment, a method is provided for applying traction to auser's spine. Two or more support belts are positioned around the user'sbody, each support belt including a back portion and right and leftfront portions. The length of at least one of the support belts isadjusted by attaching opposite ends of a strap to the right and leftfront portions of the belt, the strap having a middle section includingopposing portions coupled to one another, and guiding the strap using astrap guide coupled to the belt proximate to the back portion. The strapis coupled to the back portion of the belt between the opposite ends ofthe strap such that movement of the right and left front portions of thebelt away from the back portion of the belt causes detachment of theopposing portions of the middle section of the strap from one another.The right and left front portions of the belt are moved away from theback portion of the belt to adjust the length of the belt, thedetachable coupling of the opposing portions of the middle section ofthe strap ensuring that the right and left front portions of the beltmove in approximately equal amounts relative to the back portion of thebelt. A decompressive force is applied to the user's spine when thesupport belts are positioned around the user's body, the decompressiveforce applied by one or more supports, each support coupled between twoor more of the support belts.

Particular embodiments of the present invention may provide one or moretechnical advantages. For example, certain embodiments provide a methodfor applying traction to a user's spine using a traction device that maybe worn by a user to reduce the compressive forces on the user's spineby transferring the user's upper body weight off of the spine to theuser's hips. In particular, the decompressive forces generated by thedevice may be concentrated on the lower spine of the user, an area thatmay be commonly injured due to compressive forces. The traction devicemay also provide stabilization of the torso to prevent additionalcompressive forces in the spine due to bending and lifting by the user.Moreover, traction devices in certain embodiments may be used inassociation with other joints of the body, such as the knee or neck.Furthermore, certain embodiments provide a method of fitting a tractiondevice that is ambulatory, meaning that the device is portable andwearable during the user's daily activities. The ambulatory nature ofthe device may provide more convenience to the user and cause lessimpact on the user's daily activities than previous treatmenttechniques.

Certain embodiments may provide all, some, or none of these technicaladvantages. Certain embodiments may provide one or more other technicaladvantages, one or more of which may be readily apparent to thoseskilled in the art from the figures, description, and claims includedherein.

BRIEF DESCRIPTION OF THE DRAWINGS

To provide a more complete understanding of the present invention andthe features and advantages thereof, reference is made to the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1A is a schematic diagram showing an example traction device beingworn by a user;

FIG. 1B is a cross-sectional drawing of a portion of the traction deviceof FIG. 1A, showing example locations for lifting mechanisms associatedwith the traction device;

FIG. 1C is a cross-sectional drawing of a portion of the traction deviceof FIG. 1A, showing example alternative locations for lifting mechanismsassociated with the traction device;

FIG. 2 is a schematic diagram illustrating in more detail portions ofexample upper and lower belts of the traction device of FIG. 1A;

FIG. 3 is a schematic diagram with portions cut away showing in moredetail one of the example lifting mechanisms of the traction device ofFIG. 1A;

FIGS. 4A through 4D illustrate various views of an example liftingmechanism for use in a traction device;

FIG. 5 illustrates an example valve assembly of a traction device;

FIGS. 6A and 6B illustrate an example back belt included in a supportbelt of a traction device;

FIG. 7 illustrates another example back belt included in a support beltof a traction device;

FIG. 8 is a schematic diagram illustrating a portion of the exampletraction device of FIGS. 1A through 1C, showing portions of one of thebelts;

FIG. 9A is a top view of an example support belt and length adjustmentmechanism combination in an unadjusted position;

FIG. 9B is a top view of the example combination of FIG. 9A in anadjusted position; and

FIG. 9C is a top view of a support belt after removal of the exampleadjustment mechanism of FIGS. 9A and 9B.

DESCRIPTION OF EXAMPLE EMBODIMENTS

FIG. 1A is a schematic diagram showing an example traction device 10being worn by a user 12. In this embodiment, traction device 10 appliesdecompressive forces to the spine of user 12, which transfers bodyweight from the upper torso to the hips of user 12 and preventscompression and aggravation of lower back spinal conditions. In oneembodiment, the offloading forces are concentrated specifically on thelower spine, rather than across the entire spine. This effect is createdby decompressive forces pushing upward and downward on the lower spine.These decompressive forces are created by traction device 10, asdescribed below. In other embodiments, traction device 10 may be used tocreate tension in other portions of the body, such as the femur.

Traction device 10 includes an upper support belt 14 and a lower supportbelt 16; however in other embodiments, the decompression forces may begenerated through various combinations of one or more belts. Supportbelts 14 and 16 may be formed in any suitable manner that allowspositioning around the body of a user and transferring of adecompressive force to user 12. Example details of one embodiment ofbelts 14 and 16 are described in greater detail below in conjunctionwith FIG. 2.

Traction device 10 also includes one or more lifting mechanisms 18.Lifting mechanisms 18 generate a decompressive, or tensile, force thatmay be transferred to the spine of user 12 through support belts 14 and16. Lifting mechanisms 18 are coupled to a valve assembly (FIG. 5) tocontrol pressurization of lifting mechanisms 18. In one embodiment,lifting mechanisms 18 are coupled serially to the valve assembly;however, they may be coupled to the valve assembly in a parallel orother suitable fashion. Lifting mechanisms 18 are disposed withinpouches 19 connected to lower support belt 16 and pouches 21 connectedto upper support belt 14. Example locations about the circumference ofbelt 16 of lifting mechanisms 18 are shown more clearly in FIGS. 1B and1C. Coupling of lifting mechanisms 18 to support belts 14 and 16 isdescribed with reference to FIG. 3. Example details associated with oneparticular embodiment for lifting mechanism 18 are described in greaterdetail below in conjunction with FIGS. 4A–4D. However, in theillustrated embodiment, lifting mechanisms 18 are fluidic (for example,pneumatic or hydraulic) devices that create a decompressive, or tensile,force through fluid pressure. Lifting mechanisms 18 may also bemechanical devices. When pressurized, lifting mechanisms 18 push upwardon support belt 14 and downward on support belt 16, resulting in adecompressive force on the spine of user 12.

A proper fitting of traction device 10 about the body of user 12 isimportant. Fitting is accomplished, in part, through a pair of lockingdevices 20, one located on upper support belt 14 and one located onlower support belt 16 and through a common strap 22. Common strap 22forms a part of both upper support belt 14 and lower support belt 16 andtherefore allows uniform adjustment to both belts at the same time.Locking mechanisms 20 include a plurality of notches 24 and a latch 26for locking mechanism 20 in place at a desired notch location. Lockingmechanisms 20 may, however, be replaced with any suitable mechanism forlocking belts 14 and 16 into a desired location, such as snaps, hook andloop type fasteners and other suitable fasteners. Common strap 22 isdescribed in greater detail below with reference to FIG. 2.

In operation, user 12 places traction device 10 around his waist andadjusts belts 14 and 16 using common strap 22 to a desired tensionaround his waist. Common strap 22 facilitates obtaining uniformtightness of both support belts 14 and 16. User 12 may then lock belts14 and 16 in place using locking mechanisms 26. To apply traction to thespine of user 12, a fluid is supplied to lifting mechanisms 18 to causelifting mechanisms 18 to expand pushing belt 14 upward and belt 16downward. Because support belts 14 and 16 are tightly wrapped around thebody of user 12, this decompressive force is transferred to the user'sbody and hence his spine. This relieves stress on the spine.

Traction device 10 may be portable and wearable during everydayactivities. Thus, device 10 may be applied at home, work, play, orduring travel and at user's 12 convenience. Therefore, a user is morelikely to comply with therapy guidelines much more readily than if user12 was required to travel to a clinic for therapy. The amount of forcegenerated by the lifting mechanisms 18 may be controlled by the patientthrough a manual inflation device, or valve assembly, described ingreater detail in conjunction with FIG. 5, or may alternatively becontrolled with another suitable control device. In one embodiment,pressures generated within lifting mechanisms 18 offload approximately50% of the body weight of user 12. A relief valve (not explicitly shown)may be provided to prevent overinflation. Such a relief valve may besituated such that user 12 may instantly relieve the pressure in liftingmechanisms 18 at any time. Traction device 10 may also stabilize thetorso, while still allowing flexibility. This stabilization preventsadditional compressive forces in the spine due to bending and lifting.

FIGS. 1B and 1C are cross-sectional drawings through lines 1B—1B and1C—1C, respectively, of FIG. 1A showing more clearly example locationsfor lifting mechanisms 18 associated with traction device 10. FIG. 1Billustrates example locations for lifting mechanisms associated withtraction device 10 for normal spinal decompression use. As illustrated,four lifting mechanisms are used, with two in the general back region ofuser 12 and two located towards the front of user 12. This configurationallows application of a decompressive force to the spine yet allows user12 to perform daily operations without undue hindrance. FIG. 1Cillustrates an example alternative configuration that also restrictsmotion of user 12 from side to side, in addition to placing the spine ofuser 12 into traction. This may be particularly useful for treatingscoliosis. Scoliosis is a condition where the spine curves to one or twodirections in the thoracic and/or lumbar region. The vertebrae of thespine are twisted or tilted, which causes the ribs to protrude to oneside. By locating lifting mechanisms 18 towards the side of user 12,side-to-side motion by user 12 may be restricted and a straighteningforce may be applied to the spine to treat the spinal curvature effectsof scoliosis. Although four lifting mechanisms are illustrated in bothFIGS. 1B and 1C, any suitable number of lifting mechanisms may be used.

FIG. 2 is a schematic diagram illustrating in more detail portions ofexample upper and lower support belts of traction device 10. Uppersupport belt 14 is formed from a back belt 28 and a pair of front belts30. Some portions of front belt 30 are not illustrated in FIG. 2 forclarity of illustration. Front belt 30 is formed with a plurality ofholes 32 allowing selective adjustment of the size of upper belt 14. Inconjunction, back belt 28 includes a plurality of slits 35 for engagingfront belt 30 and a hole 34 for meshing with holes 32 in front belt 30.Front belt 30 and back belt 28 may be locked together through a rivet orother connector placed through a desired hole 32 and hole 34 on frontbelt 30 (not explicitly shown in FIG. 2). Surrounding front belts 30 andback belt 28 is an outer sleeve 31. Portions of outer sleeve 31 are cutaway in FIG. 2. Outer sleeve 31 provides an attractive look to supportbelt 14 and also may provide cushioning comfort to user 12. Outer sleeve31 may be formed from fabric or other suitable material and may beformed in a plurality of sections to facilitate selective access to backbelt 28 and front belts 30 for adjustment.

Back belt 28 includes a strap 202 intermeshed between two plates 204.Back belt 28 is a generally rigid member in the direction of generalizedsupport (up or down in this example) and is disposed within outer sleeve31 of belt 14. As described in greater detail below, a force applied toupper back belt 28 from lifting mechanisms 18 is transferred to outersleeve 31 and therefore the spine of user 12. Front belts 30 are alsogenerally rigid in the direction of support and may be formed fromplastic or other suitable material.

Top plate 202 and plates 204 are described in greater detail below withrespect to FIGS. 6A and 6B; however particular portions associated withapplication of a decompressive force to belts 14 and 16 are describedhere. The plate 204 that is positioned to the exterior of strap 202 isformed with notches 36. Notches 36 couple to portions of liftingmechanisms 18 and facilitate transferring of a decompressive force fromlifting mechanisms 18 to upper belt 14. Plate 204 is generally rigid inthe direction of support such that it may transfer a force resultingfrom lifting mechanisms “pushing” it. Plate 204 may be formed from anysuitable material that allows transferring of force from liftingmechanisms 18 to a belt 14; however in one embodiment, plate 204 isformed from plastic.

Lower support belt 16 is similar to upper support belt 14. Lower supportbelt 16 includes a back belt 40 and a pair of front belts 42. Back belt40 and front belts 42 are substantially similar to upper back belt 28and front belt 30 and include a plate 44 and a strap 46; however, plate44 is formed with notches 37 facing downward rather than upward to allowtransference of force from lifting mechanisms 18 in a downwarddirection.

Also shown more clearly in FIG. 2 is common strap 22. Common strap 22connects to both upper belt 14 and lower belt 16, allowing commonadjustment of spinal traction device 10 about the body of a user. Inthis example, hook and loop type fasteners 48, commonly known as VELCRO,are disposed on common strap 22 to secure strap 22 into place.

One of holes 32 in front belt 30, denoted by reference numeral 50, andone of holes 32 in front belt 42, denoted by reference numeral 52, arealso illustrated in FIG. 3.

FIG. 3 is a schematic diagram of traction device 10 with portions cutaway showing in more detail an example lifting mechanism 18 of tractiondevice 10. This figure may be oriented with respect to FIG. 2 by holes50 and 52. As illustrated, front belt 30 includes a notch 56, analogousto notches 36, and front belt 42 includes a notch 57, analogous tonotches 37. Lifting device 18 is coupled between belts 14 and 16 throughnotches 56 and 57 and clips 32, respectively, of lifting mechanisms 18.Access to notches 56 and 57 is provided through pouches 21 and 19, shownin FIG. 1A. Additional details of lifting mechanism 18 are described ingreater detail below in conjunction with FIGS. 4A through 4D.

In operation, in order to apply a decompressive force between upper belt14 and lower belt 16, lifting device 18 is pressurized causing adownward force on the lower end of lifting device 18, as denoted byreference numeral 58 and an upward force on the upper end of liftingdevice 18, as denoted by reference numeral 60. This in turn generatesforces in belt 30 and front belt 42 in opposite directions. Liftingmechanisms 18 may also be coupled between belts 14 and 16 at notches 36and 37 in plates 204 and 44. Restriction of lifting mechanism 18therefore results in applying a decompressive force to the spine of user12 through belts 14 and 16. Additional details of examples of suitablelifting mechanisms 18 are described in greater detail below inconjunction with FIGS. 4A–4D.

FIGS. 4A through 4D illustrate various views of an example liftingmechanism 18 for use in spinal or other traction device 10. FIG. 4A isan exploded view of lifting mechanism 18, FIGS. 4B and 4C are differentisometric views of an assembled lifting mechanism 18, and FIG. 4D is aside view of lifting mechanism 18 illustrating internal components oflifting mechanism 18 using broken lines. Although lifting mechanisms aredescribed, it should be understood that other types of supportmechanisms may be used. For example, static support mechanisms may beused that do not extend (unlike lifting mechanisms 18), but that simplyprovide static support. As described above, one or more liftingmechanisms 18 may be coupled between support belts 14 and 16 or anyother suitable supports (for example, between pins positioned in auser's bones on either side of a joint) and extended to provideseparation of support belts 14 and 16, thus reducing the compressiveforces applied to one or more of the vertebrae of user's spine (or anyother suitable joint). As is illustrated, example lifting mechanism 18has a substantially elliptical cross-section. The term “elliptical” ismeant to include all non-circular ellipses, ovals, “egg” shapes, “bean”shapes, and any other similar shapes. When lifting mechanism 18 ispositioned as a part of traction device 10, this substantiallyelliptical cross-section provides greater comfort to the user and has alower profile against the user's body than would a similar liftingmechanism having a cylindrical cross-section. Furthermore, other shapesthat conform to the user's body may also be used. However, as describedbelow, the use of such substantially elliptical or other non-circularcross-sections present problems that are not associated with acylindrical cross-section.

Lifting mechanism 18 includes a piston having a piston rod 102 and aflange 104 that is inserted into a sleeve 106. In the illustratedembodiment, piston rod 102, flange 104, and sleeve 106 each have asubstantially elliptical cross-section. However, any other appropriateshape may be used for one or more of these components. For example,flange 104 and sleeve 106 may have substantially ellipticalcross-sections and piston rod 102 may have a circular or otherappropriate cross-section. Flange 104 is configured such that itconforms to the inside of sleeve 106 and may slide inside sleeve 106. Apiston ring 108 may be positioned around the perimeter of flange 104 toform a seal between flange 104 and sleeve 106. A groove 110 may beformed around the perimeter of flange 104 to provide a seating forpiston ring 108. Piston ring 108 may have a rectangular cross-section, acircular cross-section, or any other appropriate type of cross-section.Furthermore, piston ring 108 may be fabricated from rubber or any otherappropriate material.

Since sleeve 106 has a non-circular cross-section, if the interior ofsleeve 106 is pressurized to effect the movement of piston rod 102 (asdescribed below), stresses will be developed in sleeve 106 and givesleeve 106 the tendency to deform into a cylindrical shape. This isundesirable since it may induce leakage between sleeve 106 and pistonring 108. Therefore, sleeve 106 may be fabricated from a metal, such asaluminum, or another appropriate material to withstand these stressesand prevent such deformation. In the example embodiment, sleeve 106 hasopenings at either end and thus does not form an airtight chamber intowhich air or any other appropriate fluid may be inserted to move pistonrod 102. Therefore, to form an airtight chamber, a housing is formedaround sleeve 106. The housing includes a housing bottom 112 which fitsover one end of sleeve 106 and a housing top 114 which fits over theother end of sleeve 106 and contacts housing bottom 112. Housing top 114also provides an opening 116 through which piston rod 102 may beextended. A housing ring 118 may be inserted into housing bottom 112 toprovide a seal between sleeve 106 and housing bottom 112 to prevent orreduce the leakage of air or other fluids from sleeve 106. A lower edge120 of housing top 114 may be sonically welded to an upper edge 122 ofhousing bottom 112, although housing bottom 112 and housing top 114 maybe coupled in any other appropriate manner to form a substantiallyairtight enclosure. Housing bottom 112 and housing top 114 may befabricated from plastic or any other suitable material. Furthermore,housing top 114 may be eliminated in certain embodiments and sleeve 106may have a partially enclosed first end and be bonded with housingbottom 112 at a second end. However, housing top 114 may be used whenbonding between sleeve 106 and housing bottom 112 is infeasible due tothe use of differing materials to fabricate sleeve 106 and housingbottom 112.

In particular embodiments, piston rod 102 may be hollow such that acavity 124 extends from one end of piston rod 102 to the other. Cavity124 extends through flange 104 such that air or another fluid in sleeve106 may travel through piston rod 102 in cavity 124. Therefore, a pistonrod top 126 is coupled to the end of piston rod 102 opposite flange 104to prevent this air or other fluid from escaping from sleeve 106 throughpiston rod 102. Piston rod top 126 may be sonically welded to piston rod102 or coupled to piston rod using any other suitable technique. As withpiston rod 102, piston rod top 126 may be fabricated from plastic or anyother appropriate material. Cavity 124 is provided in particularembodiments so that a spring 128 or other appropriate elastic member maybe used to connect housing bottom 112 and piston rod top 126. Spring 128is used to provide a force to retract piston rod 102 into sleeve 106when a sufficient air or other fluid pressure does not exist in sleeve106 to counteract the retraction force generated by spring 128, such aswhen traction device 10 is not in use. Housing bottom 112 and piston rodtop 126 may each include a hook point 130 which may be used to attachspring 128 to housing bottom 112 and piston rod top 126. Alternatively,any other appropriate attachment points located in any other suitablepositions may be used. Housing bottom 112 and piston rod top 126 mayalso include clips 132 for coupling lifting mechanism 18 to supportbelts 14 and 16, as described above.

As shown in FIG. 4C, housing bottom 112 also includes one or more inlets134 through which air or any other appropriate fluid may be pumped intoand released from sleeve 106. For example, inlets 134 may be configuredsuch that a hose from an associated pump may be coupled to inlets 134.Using such a pump, air or another fluid may be pumped into sleeve 106until a sufficient amount of pressure is exerted against a bottom face136 of flange 104 (shown in FIG. 4A), and against piston rod top 126 ifpiston rod 102 is hollow to cause flange 104 to move away from housingbottom 112 and thus for piston rod 102 to extend out from housing top114. Air or any other appropriate fluid may be pumped into sleeve 106through inlets 132 until piston rod 102 is in an appropriate position.As described above, multiple lifting mechanisms 18 may be coupledbetween support belts 14 and 16, and the piston rod 102 of each liftingmechanism 18 may be extended such that appropriate spacing is maintainedbetween support belts 14 and 16 and an appropriate force is applied toplace the user's spine or other joint in traction. Once this appropriateposition and force are reached, the pressure against flange 104 (andpiston rod top 126, if appropriate) are maintained to provide support tothe user and reduce compressive forces on the user's spine or otherjoint.

FIG. 5 illustrates an example valve assembly 150 of traction device 10.Valve assembly 150 may be used to connect multiple lifting mechanism 18to a pump used to pump air or any other appropriate fluid into liftingmechanism 18. For example the multiple lifting mechanisms 18 of tractiondevice 10 may be connected to a pump in series or in parallel byappropriately connecting inlets 134. For example, a hose may be coupledbetween valve assembly 150 (as described below) and a first inlet 134 ofa first lifting mechanism 18. Another hose may be coupled between asecond inlet 134 of the first lifting mechanism 18 (as illustrated inFIG. 4C, each lifting mechanism 18 may have multiple inlets 134) and afirst inlet 134 of a second lifting mechanism 18. Such a pattern may becontinued until each lifting mechanism 18 is either connected to anotherlifting mechanism 18 or to valve assembly 150. A pump may then becoupled to valve assembly 150 to pump air or another fluid into thevarious lifting mechanisms 18, as described below. Alternatively, eachlifting mechanism 18 may be individually coupled to valve assembly 150or subsets of the lifting mechanism 18 may be coupled in series and thencoupled to valve assembly 150. For example, two front lifting mechanisms18 may be coupled in series and two back lifting mechanisms 18 may becoupled in series separate from the front lifting mechanisms 18.

Valve assembly 150 provides a point at which the various liftingmechanisms 18, no matter how interconnected, may be coupled to a pump.In the illustrated embodiment, valve assembly 150 is formed integrallywith one of the lifting mechanisms 18 of traction device 10. Forexample, a housing 152 of valve assembly 150 may be formed integrallywith a housing 154 of the associated lifting device (housing 154 may beused in place of housing 114, described above). However, valve assembly150 may also be fabricated as a stand-alone device that may beassociated with traction device 10 in any appropriate manner.

Valve assembly 150 includes a valve plate 156 that includes a number ofcouplers 158 to which hoses may be coupled. For example, a hose from apump may be coupled to coupler 158 a, which is located in the center ofplate 156. Similarly, hoses leading to one or more lifting mechanisms 18or other devices to which air or another fluid is to be supplied (forexample, a lumbar pillow associated with lower support belt 14) may becoupled to couplers 158 b–158 d. Any appropriate number of couplers 158may be included in valve assembly 150. Plate 156 further includes aseries of holes, with each hole extending from a coupler 158 throughplate 156 to an upper surface 160 of plate 156. Therefore, air oranother fluid may travel from upper surface 160 of plate 156 througheach of these holes to a hose attached to the respective coupler 158,and vice versa. When assembled, plate 156 is positioned concentric toand proximate a plunger 162 and is separated from plunger 162 by anumber of O-rings 164 or other appropriate seals. Each O-ring 164 ispositioned around a respective hole in plate 156. Plunger 162 includes acenter hole 166 that extends through plunger 162 and aligns with acenter hole in plate 156 (extending from coupler 158 a). Plunger 162also includes a side hole 168 that extends through plunger 162 and islocated the same distance from the center of plunger 162 as the distancethe holes associated with couplers 158 b–158 d are located from thecenter of plate 156.

A spring 170 is positioned between plunger 162 and an upper innersurface 172 of housing 152. Spring 172 applies a force to plunger 162that causes plunger to be pressed against and form a seal with plate 156(with the aid of O-rings 164). An airtight enclosure is formed in thetop portion of housing 152 above plunger 162 by coupling plate 156 tohousing 152, for example, with one or more appropriate fasteners.Plunger 162 is coupled to a valve lever 174, which is located outside ofhousing 152. Lever 174 may be used to rotate plunger 162 or to raiseplunger 162 so as to break the seal between plunger 162 and plate 156.Furthermore, an airtight enclosure is formed between plate 156 andplunger 172 by fastening plate 156 against a lip 176 of housing 152. Forexample, holes 178 may be used to fasten plate 156 against lip 176 usingscrews or other appropriate fasteners.

When plunger 162 is in contact with plate 156, air or another fluid froma pump coupled to coupler 158a may pass through plate 156 (in the holeassociated with coupler 158 a) and then through hole 166 of plunger 162into the airtight enclosure above plunger 162. The air or other fluidthen travels back down through hole 168 of plunger 162. Where the airtravels after this depends on where hole 168 is positioned. Lever 174may be used to rotate plunger 162 such that hole 168 may be aligned witha hole in plate 156 corresponding to coupler 158 b, 158 c, or 158 d.When hole 168 is aligned with one of these holes in plate 156, the airmay then travel through the hole in plate 156 to the hose attached tothe corresponding coupler 158 b, 158 c, or 158 d. The air then travelsthrough the corresponding hose to the one or more lifting mechanisms 18or other pressurized devices attached to the hose.

This process may be repeated for the devices coupled to each coupler 158b–158 d by rotating plunger 162 so that hole 168 is aligned with theappropriate hole in plate 156. A check valve may be included in plunger162 in-line with hole 166 to prevent air or another fluid from thevarious attached pressurized devices from returning through hole 166 andthus escaping through the hole in plate 156 corresponding with coupler158 a, for example, when no pump is coupled to coupler 158 a. When auser desires to release the air or another fluid from the variousattached pressurized devices, the user may use lever 174 to lift plunger162 off of plate 156. When this happens, the air or other fluid fromeach of the devices passes from the various hoses coupled to couplers158 b–158 d through plate 156 and then back through plate 156 throughthe hole associated with coupler 158 a (if a pump is not coupled tocoupler 158 a) or through another suitable outlet.

FIG. 6A illustrates an example back belt 28 included in a support belt14 of traction device 10, viewed from the rear. Back belt 28 may becoupled to front belts 31 of support belt 14 using holes 32 and 34 andan associated connector, as illustrated in FIG. 2, with strap 202 beinginternal to plate 204 (closer to the user's body) to accommodate liftingmechanisms 18. However, it should be noted that support belt 14 mayinclude a single belt that includes the features of both back belt 28and front belts 31. Back belt 28 includes a strap 202 and a plate 204.FIG. 6B illustrates an example back belt 28 included in support belt 14of traction device 10 without plate 204 to more clearly illustrate strap202. As described above, plate 204 includes notches 36 that are used toconnect lifting mechanisms 18 to support belts 14 and 16. For example,clips 132 of a lifting mechanism 18 may be inserted into notches 36 toattach the lifting mechanism 18 to support belt 14. In the exampleembodiment, strap 202 is coupled to plate 204 at two pivots 206. Pivots206, along with a canting mechanism 208 incorporated in strap 202, allowstrap 202 to move in relation to plate 204 (and thus in relation tolifting mechanisms 18) to assist in fitting support belts 14 and 16 tothe user's body, as described below. Any appropriate component may beused to couple strap 202 and plate 204 at pivots 206 so as to allowstrap 202 and plate 204 to rotate relative to one another at pivots 206.

Strap 202 includes a first portion 210 a and a second portion 210 b thatare coupled using canting mechanism 208. In one embodiment, cantingmechanism 208 includes two hinges 212 a and 212 b. Plate 204 and cantingmechanism 208 are typically positioned on the user's back near the spinewhen the user wears traction device 10. Portions 210 typically extendfrom the user's back and around the user's sides to the user's front.When worn in such a manner, pivots 206 and hinges 212 of cantingmechanism 208 allow portions 210 to conform to the contours of theuser's body, and particularly to the areas of the thorax and the pelvis.Therefore, canting mechanism 208 may be used to more closely fit supportbelts 14 and 16 to users having a variety of different sizes and shapes,while maintaining substantial symmetry and more effective treatment.

As is illustrated in FIGS. 6A and 6B, portions 210 and canting mechanism208 may be integrally formed. For example, portions 210 and cantingmechanism 208 may be formed from a single piece of plastic and hinges212 may be formed by molding or cutting this piece of plastic into thedesired shape. Alternatively, any other suitable method of fabricatingthese components from any appropriate material may be used. Hinges 212 aand 212 b may be formed by forming or cutting slots 214 a and 214 b,respectively, in strap 202. The term “slots” is meant to include bothslits and wedges formed in strap 202. If slits are formed, the slits arepulled open to create wedges when strap 202 is coupled to plate 204. Asillustrated in FIG. 6B, slot 214 a associated with hinge 212 a begins ata first edge 216 of strap 102 and extends almost to a second edge 218 ofstrap 202. The remaining material of strap 202 between the end of slot214a and second edge 218 of strap 202 forms hinge 212 a. Furthermore, acircular or other cut-out may be formed at the end of slot 214 a nearsecond edge 218 to aid in the opening of slot 214 and to reduce theresultant stresses on hinge 212 a. Slot 214 b is formed in a similarmanner except that slot 214 b begins at second edge 218 of strap 202 andextends almost to first edge 216 of strap 202. Hinge 212 b is locatedproximate to first edge 216 and provides a different point of rotationthan hinge 212 a. Therefore, hinges 212 a and 212 b may be collectivelyreferred to as a polycentric hinge.

If slots 214 are formed as wedges in strap 202, the width of wedges 214and the angle at which wedges 214 are formed determines, at least inpart, the range of movement of portions 210. For example, the greaterthe size of wedges 214, the more range of movement that will be allowed.If slots 214 are formed as slits, the slits are opened to form wedgeshaving an appropriate size. Furthermore, the positioning of hinges 212ensures that the movement of portions 210 is complementary. For example,if an end 220 a of portion 210 a moves up, then an end 220 b of portion210 b will move up a substantially equal amount. This is because theupward movement of end 220 a will cause slot 214 a to close about hinge212 a, and this closure of hinge 214 a will in turn cause slot 214 b toopen about hinge 212 b (due to forces applied and the positioning ofpivots 206). This closure of hinge 214 b will in turn cause an upwardmovement of end 220 b. Therefore, the design of canting mechanism 208allows for the movement of portions 210 a and 210 b of strap 202 andsynchronizes this movement.

Referring again to FIG. 6A, depending upon which part of the user's bodythat back belt 200 is to be positioned around, one or more limitors 222may be used to limit the movement of portions 210 in a certaindirection. For example, if back belt 200 is to be positioned around theuser's hips with first edge 216 of strap 202 nearest to the user's legs,then limitors 222 may be positioned as illustrated to allow portions 210to move upward to accommodate the user's hips, but not allow downwardmovement of portions 210 past a certain point. Limitor slots 224 may beformed in strap 202 and may be configured and positioned such that whenportions 210 are moved downward, limitor slots 224 engage with limitors222 on plate 204 and prevent further downward movement of portions 210with respect to plate 204. In this case, limitors 222 may be peg-likeextensions from plate 204 on the side of plate 204 to which strap 202 isattached. Although limiting the downward movement of portions 210 isdescribed, it should be understood that limitors 222 and limitor slots224 may be positioned in other embodiments so as to limit the upwardand/or downward movement of portions 210.

FIG. 7 illustrates another example back belt 300 included in a supportbelt 14 of traction device 10. Back belt 300 includes a strap having twoseparate portions 302 a and 302 b and also includes a plate 304 couplingportions 302 a and 302 b. As with plate 204, lifting mechanisms 18 arecoupled to plate 304. Portions 302 are coupled to plate 304 at pivots306, such that portions 302 may move independently of plate 304. Backbelt 300 also includes a canting mechanism 308. However, unlike cantingmechanism 208 of FIGS. 6A and 6B, canting mechanism 308 is implementedusing a series of gears. In one embodiment, these gears include strapgears 310 a and 310 b, which are rotatably coupled to portions 302 a and302 b, respectively, and plate gears 312 a and 312 b, which arerotatably coupled to plate 304. Gears 310 and 312 may be fabricated fromplastic, metal, or any other appropriate material.

Gears 310 and 312 may be coupled to one another in the following manner.Gear 310 a meshes with gear 312 a, gear 312 a meshes with gear 312 b,and gear 312 b meshes with gear 310 b. Therefore, if gear 310 a isrotated, this rotation also causes gears 312 a, 312 b, and 310 b torotate. Gears 310 a and 310 b are coupled to portions 302 a and 302 b,respectively, such that when a portion 302 rotates about its respectivepivots 306, the respective strap gear 310 associated with the portion302 also rotates about the pivot 306. Since gears 310 are coupledthrough gears 312, if one portion 302 is moved upward or downward, theother portion 302 moves substantially the same distance in the samedirection.

For example, if an end 312 a of portion 302 a is raised (for example, tofit over a user's hip), then this motion will cause gear 310 a to rotatein a clockwise direction and the degree of this rotation will berelative to the distance that end 312 a is raised. The clockwiserotation of gear 310 a will in turn cause a counter-clockwise rotationof gear 312 a, and this rotation of gear 312 a will cause a clockwiserotation of gear 312 b. Finally, the clockwise rotation of gear 312 bwill cause a counter-clockwise rotation of gear 310 b, which in turnwill cause an end 312 b of portion 302 b to move substantially the samedistance upward as end 312 a was moved. Furthermore, although notillustrated in FIG. 7, back belt 300 may have limitors and limitor slots(as with back belt 200) to limit the movement of straps 302 a and 302 bin one or more directions, as described with reference to FIGS. 6A and6B above. Moreover, although two example canting mechanisms forfacilitating the manipulation of a support belt 14 to fit the contoursof a user's body while maintaining substantial symmetry are described,any other appropriate mechanisms may be used and are included within thescope of the present invention.

FIG. 8 is a schematic diagram illustrating a portion of upper supportbelt 14 of traction device 10 of FIG. 1, illustrating the movablerelationship between front belts 30 a, 30 b and back belt 28. Frontbelts 30 a and 30 b may be adjusted relative to back belt 28 toappropriately fit a user. Adjustment of front belts 30 a and 30 b withrespect to back belt 28 is referred to as a macro adjustment becauseadditional adjustments may be made through latches 24 and 26 and commonstrap 22. Lower belt 16 may be adjusted in a similar manner.

In the illustrated embodiment, back belt 28 is formed with a pair ofholes 32 for intermeshing and coupling with one of holes 33 formed infront belts 30 a and 30 b. Use of holes 32 and 33 may sometimes allowsuitable adjustments of front portions 30 a and 30 b such that a usermay pull on both 30 a and 30 b and increase the length equally from bothsides; however it is often difficult to ensure that front belts 30 a and30 b have been lengthened by the same number of holes 33. In addition,in embodiments that do not utilize holes 32 and 33, such as embodimentsthat utilize clamps or other suitable connecting mechanisms for joiningfront belts 30 a and 30 b to back belt 28, it is often difficult tolengthen belt 14 equally from both sides. If upper belt 14 is notlengthened equally from both sides, this may skew the position oflifting mechanisms 18 to an undesired position. Therefore, an adjustmentmechanism is provided that facilitates lengthening belt 14 to a suitablesize but maintains the appropriate orientation of the associated liftmechanisms 18. An example embodiment of such a mechanism is describedbelow in conjunction with FIGS. 9A through 9C.

FIG. 9A is a top view of a belt 402 in combination with an adjustmentmechanism 404 in an unadjusted position. Belt 402 may be similar toupper belt 14 or lower belt 16 and includes front portions 406 a and 406b that may be connected to a back portion 408. Belt 402 is lengthened bypulling together front portions 406 a and 406 b thus pulling the frontportions away from back portion 408. As described above, it is oftendifficult to pull equally on front portion 406 a and 406 b to maintainthe desired orientation of belt 402 about the body of a user. Whenutilizing lift mechanisms 18, this disorientation could result inimproper fitting of the belt and improper forces being applied to theuser. Therefore, an adjustment mechanism 404 is provided. Adjustmentmechanism 404 includes a strap 409 having ends 410 and 412 coupled tofront portions 406 a and 406 b, respectively. As used herein, “ends”refers generally to opposite portions of strap 409; however, ends 410and 412 are not required to be the termination of strap 409. Ends 410and 412 may couple to front portions 406 a and 406 b, respectivelythrough any suitable manner, such as snap combinations 414, 426 and 416,428. Adjustment mechanism 408 also includes a clamp 420 coupled to backbelt 408 through snap combination 424, 434. Clamp 420 includes rollersor bars 422 that guide strap 409 along back belt 408. A hook and loopmaterial, commonly known as VELCRO, is formed on strap 409 betweenrollers 422, as denoted by reference numeral 418. Strap 409 may alsoinclude this hook and loop material on other portions of it. Operationof adjustment mechanism 408 is described with reference to FIG. 9B.

FIG. 9B is a top view of the adjustment mechanism 408 and belt 402combination of FIG. 9A showing belt 402 in an adjusted position. Asshown, front portions 406 a and 406 b have been pulled together, asdenoted by reference numeral 448, thus increasing the length of belt402. Pulling front portions 406 a and 406 b together necessarily pullsstrap 409 and hook and loop portion 418 along with it. In doing so, hookand loop portion 418 detaches from each other, which causes strap 409 tobe pulled equally from both the side of 406 a and the side of 406 b.This ensures that the resulting configuration of belt 402 maintains theproper orientation for lift mechanisms such as those described above.Front belts 406 a, 406 b may then be secured to back belt 408 by rivetsor other suitable connectors 450 and 452.

FIG. 9C is a top view of the belt 402 shown in FIGS. 9A and 9B afterdetachment of adjustment mechanism 404. After belt 402 is suitablyadjusted, as described in FIG. 9B, adjustment mechanism 404 may bedetached at ends 410 and 412 as well as clamp 420, leaving the device asshown in FIG. 9C. Thus a macro adjustment for belt 402 may be effectedthat ensures proper orientation of associated lifting mechanisms, whilefine tuning of the fit or belt may be accomplished through common strap22 and locking devices 20.

Although the present invention has been described with severalembodiments, numerous changes, substitutions, variations, alterations,and modifications may be suggested to one skilled in the art, and it isintended that the invention encompass all such changes, substitutions,variations, alterations, and modifications as fall within the spirit andscope of the appended claims.

1. A method for adjusting the length of a belt having right and leftfront portions and a back portion, the right and left front portions ofthe belt each moveable with respect to the back portion of the belt, themethod comprising: attaching opposite ends of a strap to the right andleft front portions of the belt, the strap having a middle sectioncomprising opposing portions detachably coupled to one another; couplingthe strap to the back portion of the belt between the opposite ends ofthe strap such that movement of the right and left front portions of thebelt away from the back portion of the belt causes detachment of theopposing portions of the middle section of the strap from one another;and moving the right and left front portions of the belt away from theback portion of the belt to adjust the length of the belt, thedetachable coupling of the opposing portions of the middle section ofthe strap ensuring that the right and left front portions of the beltmove in approximately equal amounts relative to the back portion of thebelt.
 2. The method of claim 1, wherein the opposing portions of themiddle section of the strap comprise hook and loop material.
 3. Themethod of claim 1, wherein the opposing ends of the strap comprise aplurality of snaps.
 4. The method of claim 1, further comprisingdetaching the strap from the belt alter adjusting the belt about auser's body.
 5. The method of claim 1, further comprising coupling theright and left front portions of the belt to the back portion of thebelt after moving the right and left front portions of the belt adesired distance relative to the back portion of the belt.
 6. The methodof claim 1, wherein the strap is coupled to the right and left frontportions of the belt using snaps.
 7. The method of claim 1, wherein thestrap is coupled to the right and left front portions of the belt and tothe back portion of the belt such that the strap may be selectivelydecoupled from the belt.
 8. The method of claim 1, wherein the belt ispositioned around the user's body during initial fitting of a tractiondevice for the user.
 9. A method of fitting an ambulatory fractiondevice to a user, comprising: positioning two or more support beltsaround the user's body, each support belt comprising a back portion andright and left front portions; and adjusting the length of at least oneof the support belts, adjusting the length comprising: attachingopposite ends of a strap to the right and left front portions of thebelt, the strap having a middle section comprising opposing portionsdetachably coupled to one another; coupling the strap to the backportion of the belt between the opposite ends of the strap such thatmovement of the right and left front portions of the belt away from theback portion of the belt causes detachment of the opposing portions ofthe middle section of the strap from one another; and moving the rightand left front portions of the belt away from the back portion of thebelt to adjust the length of the belt, the detachable coupling of theopposing portions of the middle section of the strap ensuring that theright and left front portions of the belt move in approximately equalamounts relative to the back portion of the belt.
 10. The method ofclaim 9, wherein the opposing portions of the middle section of thestrap comprise hook and loop material.
 11. The method of claim 9,wherein the opposing ends of the strap comprise a plurality of snaps.12. The method of claim 9, further comprising detaching the strap fromthe belt after adjusting the belt about the user's body.
 13. The methodof claim 9, further comprising coupling the right and left frontportions of the belt to the back portion of the belt after moving theright and left front portions of the belt a desired distance relative tothe back portion of the belt.
 14. The method of claim 9, wherein thestrap is coupled to the right and left front portions of the belt usingsnaps.
 15. The method of claim 9, wherein the strap is coupled to theright and left front portions of the belt and to the back portion of thebelt such that the strap may be selectively decoupled from the belt. 16.The method of claim 9, wherein the belts are positioned around theuser's body during initial fitting of the device for the user.
 17. Amethod of applying traction to a user's spine, comprising: positioningtwo or more support belts around the user's body, each support beltcomprising a back portion and right and left front portions; adjustingthe length of at least one of the support belts, adjusting the lengthcomprising: attaching opposite ends of a strap to the right and leftfront portions of the belt, the strap having a middle section comprisingopposing portions detachably coupled to one another; coupling the strapto the back portion of the belt between the opposite ends of the strapsuch that movement of the right and left front portions of the belt awayfrom the back portion of the belt causes detachment of the opposingportions of the middle section of the strap from one another; and movingthe right and left front portions of the belt away from the back portionof the belt to adjust the length of the belt, the detachable coupling ofthe opposing portions of the middle section of the strap ensuring thatthe right and left front portions of the belt move in approximatelyequal amounts relative to the back portion of the belt; and applying adecompressive force to the user's spine when the support belts arepositioned around the user's body, the decompressive force applied byone or more supports, each support coupled between two or more of thesupport belts.
 18. The method of claim 17, wherein the opposing portionsof the middle section of the strap comprise hook and loop material. 19.The method of claim 17, wherein the opposing ends of the strap comprisea plurality of snaps.
 20. The method of claim 17, further comprisingdetaching the strap from the belt after adjusting the belt about theuser's body.
 21. The method of claim 17, further comprising coupling theright and left front portions of the belt to the back portion of thebelt after moving the right and left front portions of the belt adesired distance relative to the back portion of the belt.
 22. Themethod of claim 17, wherein the strap is coupled to the right and leftfront portions of the belt using snaps.
 23. The method of claim 17,wherein the strap is coupled to the right and left front portions of thebelt and to the back portion of the belt such that the strap may beselectively decoupled from the belt.
 24. The method of claim 17, whereinthe belts are positioned around the user's body during initial fittingof the device for the user.
 25. The method of claim 17, wherein thesupports comprise lifting mechanisms.
 26. The method of claim 17,wherein the back portion of the belt is generally rigid in the directionof the decompressive force.
 27. The method of claim 17, wherein theright and left front portions of the belt are generally rigid in thedirection of the decompressive force.